class Vote extends IdeaAttribute{ 
    final static byte POSITIVE_VALUE = 1
    final static byte NEGATIVE_VALUE = -1
	
	/** The actual value of the vote. Could be either POSITIVE_VALUE or NEGATIVE_VALUE */
	byte value

	void setValue(byte value) {
		throw new UnsupportedOperationException("Cannot set the value directly. Use up() or down() instance methods.")
	}
	
	def up() {
		this.value = POSITIVE_VALUE
	}
	
	def down() {
		this.value = NEGATIVE_VALUE
	}
}	
